This beautiful photo is a mosaic of 165 images taken when the Cassini spacecraft was directly behind Saturn, so that the rings are backlit. Notice that some very faint rings are visible far out in the system. Here is another back-lit ring photo, this time seen from above. And here is a sun-lit ring photo. And another. Explore the Cassini web page to see many other spectacular images. This is a guide to some of these images.

When Cassini was launched in 1997, there were 18 known moons of Saturn. By the time it reached Saturn in 2004, 13 others had been discovered by Earth-based telescopes. By now, 62 moons have known orbits, but if you think about it, the rings could be thought of as made of billions of moons, since there is no objective measure of moon size limits. There are 7 moons large enough to be spherical, including the second-largest in the solar system--Titan. There are 53 named moons, most less than 50 km in diameter. Cassini has been orbiting Saturn for seven years, and with its tremendously high resolution camera taking extremely close-up pictures, each moon becomes a world of fantastic interest in its own right. The images are so diverse that it is nearly impossible to show all of the interesting ones. Cassini is still healthy, and is now on its "solstice mission" that is supposed to last until 2017, when Saturn enters its summer solstice period. Mission control can alter its orbit around Saturn in complex ways to steer it close to targets such as moons, ring edges, etc.

Phoebeclose-up Most distant of the larger moons, it had one close flyby. It is probably icy, but covered with a thin layer of dark material.

Iapetus (two-faced moon) One half (the leading side) is dark as coal, while the other half (trailing side) is white as snow. It has had two close flybys. The transition between dark and white is interesting. It is thought that dark material causes absorption of heat and sublimation of the white frost or snow. Iapetus has an equatorial ridge. There is a wonderful image of Saturn taken from a time when Cassini was near Iapetus.

For the most part, Saturn's rings are extremely thin (only about 10 m!). However, the outermost part of the B ring, influenced by Mimas, has a substantial third dimension seen best at low Sun angle as in this image. There may be other moonlets up to 1 km in size in this region.

I hope this survey of the beautiful images Cassini/Huygens has produced gives you a feeling for the scope of this tremendous Saturn system. You can spend days looking at all of the images available from Cassini, and the mission is only about mid-way into its planned duration.